Blood treatment catheter assembly

Abstract

A blood treatment catheter pre-assembled with a stiffening tube is provided. The catheter includes a withdrawal lumen and a supply lumen each having distal split tube unjoined segments and an intermediate joined segment. The split tube segment of the supply lumen is provided with a sidewall aperture. The stiffening tube extends through the withdrawal split tip tube, out the distal end of the withdrawal tube, through the aperture of the supply split tip tube and through the split tip supply tube distal of the aperture, out the distal end of the split tip supply tube. When the stiffening tube is positioned inside the catheter, the aperture is adjacent to the withdrawal tube distal opening so as to minimize stiffening tube exposure and to provide a smooth exterior profile.

1. A blood treatment catheter comprising:
 first and second lumens, said lumens being in a joined segment proximal to a dividing point and in first and second unjoined tubes, respectively, distal of said dividing point, said first tube having a length greater than the length of said second tube,  
 an aperture on the sidewall of said first unjoined tube at a distance distal of said dividing point, and  
 a stiffening tube extending through the catheter, said stiffening tube passing through said second unjoined tube, through said aperture and extending distally of said aperture through said first unjoined tube;  
 wherein said aperture is at a position on said first unjoined tube a distance distal of said dividing point that is substantially equal to the length of said second unjoined tube.  
 
   
   
     2. The catheter according to  claim 1  wherein: the catheter is a hemodialysis catheter and said first lumen is a blood supply lumen and said second lumen is a withdrawal lumen. 
   
   
     3. The catheter according to  claim 2  further comprising: a beveled distal end of said second unjoined tube, said beveled end being positioned to facilitate placing said distal end of said second unjoined tube at said aperture. 
   
   
     4. The catheter according to  claim 1  wherein: the catheter is a hemodialysis catheter and said first lumen is a blood supply lumen and said second lumen is a withdrawal lumen. 
   
   
     5. The catheter according to  claim 4  further comprising: a beveled distal end of said second unjoined tube, said beveled end being positioned to facilitate plating said distal end of said second unjoined tube at said aperture. 
   
   
     6. The catheter according to  claim 1  further comprising: a beveled distal end of said second unjoined tube, said beveled end being positioned to facilitate placing said distal end of said second unjoined tube at said aperture. 
   
   
     7. The catheter according to  claim 1  further comprising: a beveled distal end of said second unjoined tube, said beveled end being positioned to facilitate placing said distal end of said second unjoined tube at said aperture. 
   
   
     8. A blood treatment catheter comprising:
 first and second lumens, said lumens being in a joined segment proximal to a dividing point and in first and second unjoined tubes, respectively, distal of said dividing point, said first tube having a length greater than the length of said second tube,  
 an aperture on the sidewall of said first unjoined tube at a distance distal of the dividing point; and  
 a stiffening tube extending through the catheter, said stiffening tube passing through said second unjoined tube, through said aperture and extending distally of said aperture through said first unjoined tube;  
 said stiffening tube being minimally exposed in a transition zone between said first and second unjoined tubes;  
 wherein said aperture is at a position on said first unjoined tube a distance distal of said dividing point that is substantially equal to the length of said second unjoined tube.  
 
   
   
     9. The catheter according to  claim 8  wherein: the catheter is a hemodialysis catheter and said first lumen is a blood supply lumen and said second lumen is a withdrawal lumen. 
   
   
     10. The catheter according to  claim 9  further comprising: a beveled distal end of said second unjoined tube, said beveled end being positioned to facilitate placing said distal end of said second unjoined tube at said aperture. 
   
   
     11. The catheter according to  claim 8  wherein: the catheter is a hemodialysis catheter and said first lumen is a blood supply lumen and said second lumen is a withdrawal lumen. 
   
   
     12. The catheter according to  claim 11  further comprising: a beveled distal end of the second unjoined tube, said beveled end being positioned to facilitate placing said distal end of said second unjoined tube at said aperture. 
   
   
     13. The catheter according to  claim 8  further comprising: a beveled distal end of said second unjoined tube, said beveled end being positioned to facilitate placing said distal end of said second unjoined tube at said aperture. 
   
   
     14. The catheter according to  claim 8  further comprising: a beveled distal end of said second unjoined tube, said beveled end being positioned to facilitate placing said distal end of said second unjoined tube at said aperture. 
   
   
     15. A hemodialysis catheter comprising:
 supply and withdrawal lumens positioned within a joined segment proximal to a dividing point and located in first and second unjoined tubes distal of said dividing point, said first unjoined tube containing said supply lumen having a length greater than the length of said second unjoined tube having said withdrawal lumen,  
 an aperture on the sidewall of said first unjoined tube at a distance distal of said dividing point, and  
 a stiffening tube extending through the catheter, said stiffening tube passing through said second unjoined tube, through said aperture and extending distally of said aperture through said first unjoined tube,  
 said stiffening tube being minimally exposed in a transition zone between said first and second unjoined tubes;  
 wherein said aperture is at a position on said first unjoined tube a distance distal of said dividing point that is substantially equal to the length of said second unjoined tube.  
 
   
   
     16. The catheter according to  claim 15  further comprising: a beveled distal end of said second unjoined tube, said beveled end being positioned to facilitate placing said distal end of said second unjoined tube at said aperture. 
   
   
     17. The hemodialysis catheter according to  claim 16  wherein: when the stiffening tube is removed while the catheter is positioned in a blood vessel, said beveled end faces away from the vessel wall to prevent said second tube from being suctioned against the vessel wall. 
   
   
     18. The hemodialysis catheter of  claim 15  wherein: said aperture is a slit that substantially recloses when said stiffening tube is withdrawn. 
   
   
     19. The hemodialysis catheter according to  claim 15  further comprising: a second stiffening tube extending through said first lumen proximal of said dividing point. 
   
   
     20. The method of placing a blood treatment catheter in the patient wherein the catheter has first and second lumens in a joined segment proximal to a dividing point and having the first and second lumens in first and second unjoined tubes distal of the dividing point, the first tube having a length greater than the length of the second tube, comprising the steps of:
 providing a stiffening tube extending through the second tube and through an aperture in the sidewall of the first tube and extending distally of said aperture through the first tube to couple said tubes, said stiffening tube being minimally exposed in a transition zone between the first and second tubes to provide an assembly of a catheter and stiffening tube wherein the first and second unjoined tubes are coupled together, said aperture being at a position on said first unjoined tube a distance distal of said dividing point that is substantially equal to the length of said second unjoined tube,  
 inserting said assembly in a patient until the ends of the catheter are at a desired location within the patient, and  
 withdrawing the stiffening tube from the assembly to uncouple the first and second tubes.  
 
   
   
     21. A blood treatment catheter comprising:
 first and second lumens, said lumens being in a joined segment proximal to a dividing point and in first and second unjoined tubes, respectively, distal of said dividing point, said first tube having a length greater than the length of said second tube,  
 an aperture on the sidewall of said first unjoined tube at a distance distal of said dividing point, and  
 a stiffening tube capable of passing through said second unjoined tube, through said aperture and extending distally of said aperture through said first unjoined tube;  
 wherein said aperture is at a position on said first unjoined tube a distance distal of said dividing point that is substantially equal to the length of said second unjoined tube.  
 
   
   
     22. The catheter of  claim 21  wherein:
 the catheter is a hemodialysis catheter and said first lumen is a blood supply lumen and said second lumen is a withdrawal lumen.  
 
   
   
     23. The catheter of  claim 21  further comprising: a beveled distal end of said second unjoined tube, said beveled end being positioned to facilitate placing said distal end of said second unjoined tube at said aperture.